Holt’s term as Prime Minister dramatically ended a year after he became Prime Minister when he disappeared while swimming at Cheviot Beach near Portsea, Victoria, and was presumed drowned.

On Sunday 17 December 1967, Holt and some friends drove to one of his favorite swimming and snorkeling spots, Cheviot Beach on Point Nepean near Portsea, on the eastern arm of Port Phillip Bay. Holt decided to go swimming, although the surf was heavy and Cheviot Beach was notorious for its strong currents and dangerous rip tides.

Ignoring his friends’ pleas not to go in, Holt plunged into the surf and quickly disappeared from view.

Fearing the worst, his friends raised the alert.

Within a short time the beach and the water off shore was being searched by a large contingent of police, Royal Australian Navy divers, Royal Australian Air Force helicopters, Army personnel from nearby Point Nepean and local volunteers.

This quickly escalated into one of the largest search operations in Australian history, but no trace of Holt could be found.

Two days later, on 19 December 1967, the government made an official announcement that Holt was presumed dead, with a police spokesperson famously stating “The search has come to a dead halt” (“halt” is usually pronounced like “Holt” in Australia).

Holt’s body was never found and no official investigation was undertaken.

American newlyweds, Glen and Bessie Hyde, disappeared while attempting to run the rapids of the Colorado River through Grand Canyon, Arizona in 1928.

Glen Hyde had some experience with river running, having traveled the Salmon and Snake Rivers in Idaho with “Cap” Guleke, an experienced river runner, in 1926.

Bessie was more of a novice. In 1928, Hyde built his own boat, a twenty foot wooden sweep scow, the type used by river runners of that time in Idaho. The couple set off down the canyons of the Green and Colorado Rivers in October 1928, as a honeymoon adventure trip. Glen wanted to set a new speed record for traveling through the Grand Canyon, while also putting Bessie in the record books as first documented woman to run the canyon.

A search was launched when the Hydes did not return to Idaho by December. In mid-December, a search plane spotted their scow adrift around river mile 237; it was upright and fully intact, with the supplies still strapped in. A camera recovered from the boat revealed the final photo to have been taken near river mile 165, probably on or about November 27.

Will Castro ever be found?

Just like wierd theories emerged following Castro’s disappearance, the same happened ater Holt and the Hyde’s disappeared.

In Castro’s case, we are told marine spirits have a hand in the whole affair.

The romance of the story of the Hydes, coupled with the lack of any conclusive evidence as to the fate of the Hydes, has led to a number of legends and rumors.

An elderly woman on a commercial Grand Canyon rafting trip in 1971 announced to other rafters that she was Bessie Hyde, and that she had stabbed her abusive husband to death and escaped the canyon on her own. The woman later recanted this story.

There was some speculation after the death of famed rafter Georgie Clark in May 1992 that she was really Bessie Hyde, due to some documents and a pistol found in her effects, but no conclusive evidence for such a link was ever found, not to mention that Clark and Hyde do not look alike in photos.

In Harold Holts’ case, the speculations were more intense, probably because he was a politcal figure.

There were many rumours surrounding Holt’s disappearance, including claims that he had committed suicide or faked his own death in order to run away with his mistress.

The mystery became the subject of numerous urban myths in Australia, including persistent claims that he was kidnapped (or rescued) by a Chinese submarine, or the far-fetched claim that he had been abducted by a UFO.

In 1983, British journalist Anthony Grey published a controversial book in which he claimed that Holt had been an agent for the People’s Republic of China and that he had been picked up by a Chinese submarine off Portsea and taken to China.

Such conspiracy theories rely on the fact that the bodies of the people involved were never found.